1. Field of the Invention
The invention concerns a method for detaching the wings from poultry bodies by effecting cuts on both sides of the plane of symmetry of the poultry body while lifting the wings away from the poultry body and an apparatus for carrying out this method having conveyor means for conveying the poultry body along its plane of symmetry with the neck portion leading, whereby said poultry bodies pass through a wing detaching device formed by pairs of separating tools arranged symmetrically on either side of the conveyor means and in a mirror inverted manner, in the vicinity of which guide means for seizing and drawing the wings away from the poultry body are arranged, each said separating tool being formed as a knife blade whose cutting edge extends essentially along the path of the poultry bodies.
2. Prior Art
Various embodiments of such apparatus are known.
For example, EP-B1-0 312 881 discloses an apparatus, whereby in one embodiment two separating tool pairs operating sequentially are employed. The function of the first separating tool pair, which is equipped with rotationally driven circular knives, is first to detach the wing tendons in order to enable the lifting of the wing joints out of the body's sockets before the second separating tool becomes comes into operation. By means of this lifting operation, a bone-free space between the wing joint condyle and glenoid cavity is to be achieved, so that the subsequent cut through this space made with the knife blades of the second separating tool pair allows the wings to be detached without causing bone splinters.
Another apparatus of this type is disclosed in U.S. Pat. No. 4,016,624. In this apparatus the poultry bodies are pushed forward with their rear portions leading and the wings, while being held spread or extended, are cut off by controlled knife blades, the cut being guided such that the main wing tendons are severed in an earlier phase. A further apparatus for detaching wings is known from EP-A1-0 431 607. In this apparatus, the wings are detached by means of a pair of rotationally driven circular knives in the same manner as occurs in the apparatus described in U.S. Pat. No. 4,424,608.
In detaching the wings from poultry bodies, particularly when the subsequent processing of the poultry body is aimed at obtaining breast meat in the form of fillets, it is important that in addition to avoiding bone splintering in the area of detachment, the wings are separated with as little loss of fillet meat as possible.
The results obtained by the above described apparatus do not, in particular, satisfy this last requirement, so that the achievable yield of fillet meat is thus reduced.
3. Objects of the invention
It is a general object of the invention to overcome the drawbacks associated with said prior art apparatus.
It is a particular and essential object of the present invention to achieve the separation of wings from poultry bodies while retaining as much fillet meat as possible.
It is a further most important object of this invention to perform such processing without the formation of bone splinters.